The former boss of Close Up is certain the network will replace the current affairs show with a "light and fluffy magazine" programme, driving viewers to the competition.
Bill Ralston, who was head of news and current affairs from 2003 to 2007, said TVNZ was on "a quest for ratings" and would replace the hard-hitting show with something more populist.
"They'll just do anything for money and they think they can get more ratings out of a far less serious or intelligent product than Close Up currently is. All they'll do is shove more audience to John Campbell, who's doing some fairly serious current affairs material."
The current boss of TVNZ news and current affairs, Ross Dagan, said the network wanted to reinvent the early evening slot "to present the stories of the day in a way that is very different to what has gone before".
"Everyone on the show is aware that traditional current affairs formats are losing favour with audiences, and this team has set the bar for what's possible. However ... the company's view is that this format has simply run its course."